It is known to use vehicles, which have spreading devices to spread fertilizers and other particulate materials. In the case of a fertilizer spreader, typically the vehicle is a truck or trailer which carries a hopper for the fertilizer. A conveyor belt typically forms the floor of the hopper and, when the conveyor belt is activated, conveys the fertilizer to an exit at one end of the hopper. The exit usually is formed by a door which is slidable upwardly and downwardly to adjust the size of the opening forming the exit. In the usual case, fertilizer leaving the hopper falls onto a spreader device which spreads the fertilizer.
To date, a number of problems have been encountered with such spreaders. For instance, it has been found difficult to co-ordinate the rate of dispersal of the fertilizer with the speed of the spreader across the ground. This has been found to be particularly so where the drive for the conveyor is taken from a power-take-off or the like in the prime mover.
Steps have been taken to co-ordinate dispersal by linking the conveyor and other dispersal means to a ground wheel or the like of the spreader. However, typically such linkage as have been provided to date have included a number of drawbacks.
Indeed, typically the arrangements provided to date have been relatively complex in the manner in which the drive is transmitted to the dispersal means. This has made maintenance and repair in the field, when they have become necessary, relatively difficult to achieve.
Also, drive arrangements to date have been provided in a manner which leaves typically relatively complex gear trains and the like open or otherwise exposed to fertilizer, dust, mud and water action. Such action often leads to corrosion, and jamming and clogging, of the drive means.
It is an object of at least one embodiment of this invention to come some way in overcoming the abovementioned problems or at least to provide the public with a useful choice. Other objects of this invention will become apparent from the following description.